Thousanow to the landmark case that could determine how prenups are enforced in the future. A judge sided with a woman who said her husband promised to tear up their prenup but never did. Our john muller has that story for us. Reporter: Liz petrakis on her wedding day that went from there to this. What made her divorce such a disgusting process? A prenuptial agreement she signed four days before her wedding day stipulating her husband peter would keep all of his $20 millioneal estate empire if they ever broke up. He said, you know, let's just leave it -- you sign it, we're going to throw -- I'll throw it out once we have children and that was what was promised me and I took that dear to my heart. Reporter: Peter never did rip up the prenup when the kids came. When the couple split, disspent seven years trying to do something that has never been done before. Convince the court to void a prenup. The real sad part about it is that, yes, the family is destroyed and do I wish -- Reporter: Now her long fight has paid off. In february a court upheld two prior court rulings to void the prenup on grounds it was fraudulently induced. What's important to me is trying to help -- trying to make a difference and trying to save a life because divorce almost took my life. Okay. I almost lost my life. Reporter: She may have turned divorce proceedings upside down. Giving greater credibility to the oral promise of tearing it up than they did the written prenup agreement. And that unusual. I'm here to tell you i survived and so can you. Reporter: Now an expert and a ground breaker, liz has founded a company to help people get through divorces, but her own battle isn't quite finished yet. With the prenup issue finally behind her, at long last her own divorce proceedings can finally begin. I wish my family would have still been together but, unfortunately, sometimes money gets the best of people. Reporter: Now we did reach out to the husband for comment and did not hear back. Truly a landmark case, guys. Unanimous decision in her favor. Yes, the third court that upheld it. Thanks. Get back over to sam.

This transcript has been automatically generated and may not be 100% accurate.

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